1,773 research outputs found
Self interacting Brans Dicke cosmology and Quintessence
Recent cosmological observations reveal that we are living in a flat
accelerated expanding universe. In this work we have investigated the nature of
the potential compatible with the power law expansion of the universe in a self
interacting Brans Dicke cosmology with a perfect fluid background and have
analyzed whether this potential supports the accelerated expansion. It is found
that positive power law potential is relevant in this scenario and can drive
accelerated expansion for negative Brans Dicke coupling parameter . The
evolution of the density perturbation is also analyzed in this scenerio and is
seen that the model allows growing modes for negative .Comment: 8pages, 5 figures, PRD style, some changes are made, figures added,
reference added. To be published in Int. J. Mod. Phys.
Colorimetric Assessment of BCR-ABL1 Transcripts in Clinical Samples Via Gold Nanoprobes
Gold nanoparticles functionalized with thiolated oligonucleotides (Au-nanoprobes) have been used in a range of applications for the detection of bioanalytes of interest, from ions to proteins and DNA targets. These detection strategies are based on the unique optical properties of gold nanoparticles, in particular, the intense color that is subject to modulation by modification of the medium dieletric. Au-nanoprobes have been applied for the detection and characterization of specific DNA sequences of interest, namely pathogens and disease biomarkers. Nevertheless, despite its relevance, only a few reports exist on the detection of RNA targets. Among these strategies, the colorimetric detection of DNA has been proven to work for several different targets in controlled samples but demonstration in real clinical bioanalysis has been elusive. Here, we used a colorimetric method based on Au-nanoprobes for the direct detection of the e14a2 BCR-ABL fusion transcript in myeloid leukemia patient samples without the need for retro-transcription. Au-nanoprobes directly assessed total RNA from 38 clinical samples, and results were validated against reverse transcription-nested polymerase chain reaction (RT-nested PCR) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The colorimetric Au-nanoprobe assay is a simple yet reliable strategy to scrutinize myeloid leukemia patients at diagnosis and evaluate progression, with obvious advantages in terms of time and cost, particularly in low- to medium-income countries where molecular screening is not routinely feasible. Graphical abstract Gold nanoprobe for colorimetric detection of BCR-ABL1 fusion transcripts originating from the Philadelphia chromosome
Obtenção de geléia de açaí branco (Euterpe oleracea, Mart Var. Branco).
O açaizeiro (Euterpe oleracea, Mart) é uma palmeira exuberante da flora tropical, que a partir de seus frutos, obtém-se uma bebida substancial e nutritiva. Destacando-se a variedade açaí branco, pouco aproveitado na região Norte, mas que necessita ter a propagação da espécie para gerar aumento em produção e comercialização, pois agora o açaí desperta não só o interesse nacional como internacional. O presente trabalho teve por objetivo a produção de geléia artesanal a partir da bebida açaí branco com adição de componentes naturais, como uma alternativa de conservação agregando assim valor à bebida e proporcionando melhoria de renda para a população rural. Foram realizados ensaios laboratoriais para a obtenção de uma geléia à base de albedo de laranja (fonte de pectina), suco de limão (acidulante) e açúcar (sacarose de cana de açúcar), produto A e outra geléia utilizando pectina comercial (de alto grau de metoxilação), suco de limão e açúcar, produto B. Realizaram-se determinações das características físico-químicas e microbiológicas para a matéria-prima e para o produto final, e utilizou-se análise sensorial nos produtos A e B para verificar a sua aceitação. Os resultados das análises microbiológicas para o produto final atestaram sua produção dentro de condições higiênico-sanitárias satisfatórias. A análise sensorial evidenciou que o produto A obteve maior aceitação que o produto B. A geléia com albedo apresentou 76,16% de aceitação, pH de 4,01 (baixa acidez), teor em proteínas (1,05%) e de alto valor energético (281,80 Kcal/100g). O processamento de geléia de açaí branco usando albedo de laranja, suco de limão e açúcar é viável podendo vir a ser um futuro próximo aproveitado pelas agroindústrias como uma das maneiras de conservar o açaí branco
A Double Philadelphia Chromosome-Positive Chronic Myeloid Leukemia Patient, Co-Expressing P210 BCR-ABL1 and P195 BCR-ABL1 Isoforms
info:eu-repo/semantics/publishedVersio
The November, 1st, 1755 Tsunami in Morocco: Can Numerical Modeling Clarify the Uncertainties of Historical Reports?
Pólen de abelhas indígenas sem ferrão Melipona fasciculata e Melipona flavolineata: caracterização físico-química, microbiológica e sensorial.
A Novel BCR-ABL1 Mutation in a Patient with Philadelphia Chromosome-Positive B-Cell Acute Lymphoblastic Leukemia
Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) represents the most common genetic subtype of adult ALL (20%-30%) and accounts for approximately 50% of all cases in the elderly. It has been considered the subgroup of ALL with the worst outcome. The introduction of tyrosine kinase inhibitors (TKIs) allows complete hematologic remission virtually in all patients, with improved disease-free survival and overall survival. Nevertheless, the emergence of resistant mutations in BCR-ABL1 may require different TKI strategies to overcome the patient's resistance and disease relapse. Here, we report a Ph+B-ALL case with persistent minimal residual disease (MRD) after treatment with dasatinib. The patient expressed the P190BCR-ABL1 isoform and a novel BCR-ABL1 mutation, p.Y440C. The latter is in the C-terminal lobe of the kinase domain, which likely induces deviations in the protein structure and activity and destabilizes its inactive conformation. The treatment was substituted by bosutinib, which binds to the active conformation of the protein, prior to allogeneic bone marrow transplant to overcome the lack of a complete response to dasatinib. These findings strengthen the importance of BCR-ABL1 mutational screening in Ph+ patients, particularly for those who do not achieve complete molecular remission.info:eu-repo/semantics/publishedVersio
Specific Antiproliferative Properties of Proteinaceous Toxin Secretions from the Marine Annelid Eulalia sp. onto Ovarian Cancer Cells
The Portuguese Foundation for Science and Technology (FCT) funded project WormALL (PTDC/BTA-BTA/28650/2017) plus the grants SFRH/BD/109462/2015 to A.P.R., and CEECIND/02699/2017 to A.R.G. The Applied Molecular Biosciences Unit-UCIBIO is financed by national funds from FCT, ref. UIDB/04378/2020. FCT, along with the European Regional Development Fund (ERDF) through the COMPETE 2020-Operational Programme for Competitiveness and Internationalisation also funded the projects: POCI-01-0145-FEDER-007440 (UID/NEU/04539/2019), POCI-01-0145-FEDER-016428 (SAICTPAC/0010/2015), POCI-01-0145-FEDER-029311 (PTDC/BTM-TEC/29311/2017), POCI-01-0145-FEDER-30943 (PTDC/MEC-PSQ/30943/2017) and PTDC/MED-NEU/27946/2017. The work was also funded by the National Mass Spectrometry Network (RNEM) under the contract POCI-01-0145-FEDER-402-022125 (ref.: ROTEIRO/0028/2013).As Yondelis joins the ranks of approved anti-cancer drugs, the benefit from exploring the oceans' biodiversity becomes clear. From marine toxins, relevant bioproducts can be obtained due to their potential to interfere with specific pathways. We explored the cytotoxicity of toxin-bearing secretions of the polychaete Eulalia onto a battery of normal and cancer human cell lines and discovered that the cocktail of proteins is more toxic towards an ovarian cancer cell line (A2780). The secretions' main proteins were identified by proteomics and transcriptomics: 14-3-3 protein, Hsp70, Rab3, Arylsulfatase B and serine protease, the latter two being known toxins. This mixture of toxins induces cell-cycle arrest at G2/M phase after 3h exposure in A2780 cells and extrinsic programmed cell death. These findings indicate that partial re-activation of the G2/M checkpoint, which is inactivated in many cancer cells, can be partly reversed by the toxic mixture. Protein-protein interaction networks partake in two cytotoxic effects: cell-cycle arrest with a link to RAB3C and RAF1; and lytic activity of arylsulfatases. The discovery of both mechanisms indicates that venomous mixtures may affect proliferating cells in a specific manner, highlighting the cocktails' potential in the fine-tuning of anti-cancer therapeutics targeting cell cycle and protein homeostasis.publishersversionpublishe
Avaliação de ferramentas na furação de laminados compósitos
Drilling of polymeric matrix composite structuresThe development of cutting tools becomes a challenge to the industry of composite materials to obtain high
quality holes, minimizing damage. This work aims to examine the influence of various parameters such as feed rate and tool
geometry on thrust forces developed during drilling operations and on the extent of damage.
In this work, a comparative study of tool geometry with the aim of reducing the associated damage during drilling process
is presented. In the end a good combination of tool geometry and drilling parameters based on experimental work will be
presented.O desenvolvimento de ferramentas de corte torna-se um desafio à indústria de materiais compósitos, na obtenção
de furos de elevada qualidade, minimizando o dano. Este trabalho visa analisar a influência de vários parâmetros, tais como
o avanço e a geometria de ferramenta, nas forças desenvolvidas durante a furação e na extensão do dano.
Neste artigo é apresentado um estudo comparativo de geometrias de broca com o objectivo de reduzir o dano associado à
furação, que permitirá determinar qual a melhor selecção de parâmetros de furação, atendendo às diferentes geometrias de
ferramenta
General Framework for phase synchronization through localized sets
We present an approach which enables to identify phase synchronization in
coupled chaotic oscillators without having to explicitly measure the phase. We
show that if one defines a typical event in one oscillator and then observes
another one whenever this event occurs, these observations give rise to a
localized set. Our result provides a general and easy way to identify PS, which
can also be used to oscillators that possess multiple time scales. We
illustrate our approach in networks of chemically coupled neurons. We show that
clusters of phase synchronous neurons may emerge before the onset of phase
synchronization in the whole network, producing a suitable environment for
information exchanging. Furthermore, we show the relation between the localized
sets and the amount of information that coupled chaotic oscillator can
exchange
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